Study The Performance Evaluation of Radio over Optical Fiber System with Optical OFDM using Different Modulation Techniques

This paper illustrates that the performance evaluation of radio over optical fiber (RoF) optical link has been analyzed with optical orthogonal frequency division multiplexing technique (OOFDM) through used different modulations schemes 4 -QAM, 16 -QAM, and 64 -QAM for single-channel. The new proposed system has used a combination of OFDM-RoF architecture and compare the performance of the network for different digital modulation schemes with 15 Gpbs data rate and 5.8 GHz radio frequency (RF), for the optical fiber lengths (20 up to 50) km to compensate the dispersion and other effects of distortion of wireless networks. The performance analysis is based on the optical spectrum of the transmitted signal, constellation diagrams and symbol error for four and eight channels. We can observe that the signal doesn't have any dispersion after 20 km of optical fiber length for the 4-QAM with OFDM technique, as well as, the system can be done well within 50 km of optical fiber length. In other words, the dispersion effect on the signal after 20 km of fiber length is less than after 50 km, which has distorted with a large dispersion. Therefore, the simulation results show that the 64-QAM-OFDM-RoF system gives the highest value of the symbol error. We have used Optisystem "version 14" as a simulation software package.